The maximum IP packet size that can be transmitted to a remote agent without performing pre-fragmentation. The value 0 disables this feature. If enabled, the smallest size the system will use is 68, even if a smaller size is specified. This is to comply with the minimum IP packet size requirement per RFC 791.

When set to NO, an ICMP message will be sent if a frame needs fragmentation and the DF bit is set. This is the standard behavior. When set to YES, it forces pre-fragmentation of large IP frames before they are sent to the remote agent, even if the frame has the DF bit set. This behavior is not standard and prevents MTU discovery mechanisms.